to Exempt 20-Minute Fire Windows from Hose Stream Test Fails
Committee action in support of code change proposal FS135, submitted
by William O'Keeffe with SAFTI FIRST, which would exempt 20-minute
fire windows from the hose stream test requirement, was disapproved
yesterday during the International Building Code Fire Safety hearings
According to code documents, the proposal "is a clarification
and addition to the code to specifically address the rating requirements
for interior windows. The more correct terminology for section 7126.96.36.199
should be 'area' limits, rather than 'size' limits. The new proposed
section 7188.8.131.52 addresses 20-minute windows tested to NFPA 257
now specified in Table 715.5 for ½-hour fire partitions.
Since a ½-hour fire resistance rated fire partition assembly
is tested to ASTM E 119 without the hose stream test, and fire doors
tested for 20-minutes as required in Table 715.4 are not subject
to the hose stream test, for consistency in the code, the fire window
component of a ½-hour fire partition should be likewise exempt
from the hose stream test under NFPA 257."
Based on the fact that ASTM E 119 does not require the hose stream
test for partitions qualifying for a 30-minute fire rating and Section
715.4.3 allows 20-minute rated fire doors to be tested without the
hose stream test, the committee agreed that the hose stream test
should not be required for a 20-minute rated fire protection window.
Thom Zaremba, representing Pilkington Fire Protection Glass NA
Inc., spoke against the motion. According to Zaremba's public comments
in the code documents, "Other than adding symmetry to the code,
there is no technical justification for the committee's support
of this proposal. It is true that 1/2-hour fire-resistance rated
fire partitions forming the subject of this proposal are tested
to ASTM E 119 without the hose stream test. It is also true that
20-minute fire doors may be tested without the hose stream test.
However, symmetry does not always assure an adequate level of fire
safety and it is not true that exemptions from hose-stream testing
for wall materials and doors should be extended to fire windows."
Zaremba explained that exempting wall materials from the hose stream
test recognizes that the types of materials used in fire-resistance
rated walls are not likely to degrade sufficiently by the end of
a 1/2 hour test to warrant hose stream testing; exempting 20-minute
doors from the hose stream test recognizes that it is unlikely that
fuel loads will be stacked in front of doors, blocking access through
doorways. However, the glass used in fire windows cannot be compared
to the types of materials used in fire-resistance rated walls.
"Tempered glass is not the same as the materials that are
going to be found in the products we're talking about," Zaremba
said during the hearing. "There is simply no structural glazing
strength to a tempered product that has been exposed to a fire for
According to Zaremba, "as soon as tempered glass experiences
a significant temperature delta it disintegrates. For that reason,
even when subjected to a fire test for only a few minutes, tempered
glass can fail catastrophically when subjected to the hose stream
test. If adopted, FS135 would make the testing of fire windows more
symmetrical to wall materials and doors in 1/2-hour fire partitions.
However, glass is not the same as the opaque materials used in walls
and the fire loads experienced by fire windows can be far greater
than those experienced by doors."
Code consultant Bill Koffel agreed.
"This code has never allowed fire-protection glass of any
kind without a hose stream test," said Koffel. "We have
not allowed any other glass product to be tested without a hose
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